1. Field of the Invention
The invention relates to rural mailboxes, particularly support apparatus that make the mailbox resistant to damage by being struck by a snow plow, car or truck.
2. Description of the Related Art
Urban mailbox posts have long since been a source of constant maintenance and damage repair. If proper upkeep is not provided, the result is often rather unsightly.
The greatest potential damage to a mailbox comes from a snow plow moving down the street at a moderate to high rate of speed. Attempting to do the best job possible of clearing the street, the plow gets as close to the edge of the road without hitting the mailboxes. Even if the snow plow operator misses the mailbox, the snow trailing off the plow blade has been known to completely destroy even the sturdiest mailbox posts.
U.S. Post Office specifications require that the mailbox extend to the road, so that the mail carrier can deliver the mail without leaving his/her vehicle. To remove the mail, the homeowner must stand in the street, putting the person close or in the actual path of traffic. The first sign or sound of approaching traffic usually results in the prudent person moving toward the curb.
Roadside mailbox supports come in an wide variety of designs. These range from the basic 4.times.4 post support to elaborate decorative designs.
The most basic of these designs uses a 4.times.4 inch wooden post with its members lap jointed together. This design is rigid and has been weakened by the lap joint construction. The half lap joint that locks the two pieces together actually removes about half the wood and, correspondingly, half the holding strength. The original 4.times.4 post is now actually 2.times.4 at this joint. This joint is where all the force is exerted when struck by an automobile or plow. Almost always, the support fails at this location and is a complete loss.
Numerous attempts have made to achieve crash protection for mailbox supports.
U.S. Pat. No. 3,870,262, issued to Manning, Jr. on Mar. 11, 1975, discloses a mailbox support that pivots when struck by a vehicle. However, the mailbox and its support bar slip from its bearing supports and fall to the ground along the edge or in the roadway. Once laying on the ground, it is subject to additional damage, can be easily moved substantial distances or be lost in the snow.
U.S. Pat. No. 4,187,978, issued to Dowker on Feb. 12, 1980, discloses another pivoting mailbox that is held by a shear pin. Once the mailbox is struck, the pin is sheared and the box is freed to pivot. This pin can only be sheared one time and then must be replaced. At this point the mailbox assembly is unusable.
U.S. Pat. No. 4,667,918, issued to Page on May 26, 1987, and U.S. Pat. No. 4,893,747, issued to Roth on Jan. 16, 1990, both disclose mailbox supports that allow the mailbox to rotate but first a pin or latch has to be activated. While these designs permit the homeowner to access the mail in the box without entering the street, they do not protect the mailbox from impacts from cars or snowplows.
U.S. Pat. No. 4,130,239, issued to Belsheim on Dec. 19, 1988, and U.S. Pat. No. 4,995,576, issued to Kieswetter on Feb. 26, 1991, both disclose similar pivoting actuation when struck from the side. Both discloses the use of a pipe inside a pipe at an angle to give the mailbox assembly a pivot to spin around. The angle of the pivot pipe uses the uncertainty of gravity alone to attempt to return the mailbox to its original position. Also, wind could cause the mailbox to sway in an unsightly manner. The mailbox also must leave its horizontal orientation and raise upwards at an angle as it rotates through a possible full circle. The speed of pivoting is a function of the force striking the mailbox. Gravity is the only restoring force that places the mailbox back into position once struck.
U.S. Pat. No. 3,899,150, issued to Racquet on Aug. 12, 1975, discloses the use of a long torsion spring inside a round pipe support that is said to yield to a sideward load and then return the mailbox to its original position. Frictional variations due to the introduction of water, salt or sand into the mechanism could affect the return position and result in the return position being different that the original position.
U.S. Pat. No. 5,167,364, issued to Wenning on Dec. 1, 1992, discloses the use of an internally grooved cam slot to allow the mailbox to rotate about the mailbox post. This design requires a round pipe to fit snugly within a square metal tube. Also, bearings would be necessary to assure a smooth and consistent rotatable motion. Further, cutting the complex three-dimensional curved cam path around the internal pipe is difficult. This results in this apparatus being expensive to manufacture.
U.S. Pat. No. 4,172,579, issued to Steinman on Oct. 30, 1979, discloses a spring-detent design which retains the mailbox support in either the normal "facing the road" position or 90 degrees left or right of that position. Once the mailbox is dislodged, the homeowner must manually correct the position. This design also allows the assembly to be rotated 360 degrees and stop anywhere during its rotation. Friction between the surfaces in contact would have a great impact on performance, thus susceptible to being adversely effected by salt and sand. Also, the design permits the mailbox to swing upwards.
A mailbox support that is virtually maintenance free, enables the homeowner to turn the mailbox sidewise to retrieve the mail, pivots when struck yet returns automatically to its original position with a minimum of vertical motion and is inexpensive to manufacture, is not found in the prior art.